Date of Award


Degree Name

MS in Biomedical Engineering


Biomedical and General Engineering


College of Engineering


Lily Laiho

Advisor Department

Biomedical and General Engineering

Advisor College

College of Engineering


Skin cancer is a prevalent disease that globally affects 2-3 million people per year [1]. This number is expected to grow tenfold as depletion of the ozone layer contributes to harsher rays reaching Earth’s surface [2]. A common way to protect against those ultraviolet waves is to apply sunscreen, however, recent reports call into question the safety of some active ingredients as they can enter through the skin into the bloodstream [3]. This thesis aims to investigate an alternative solution that uses bovine sphingomyelin (BSM) as photoprotective solution against UV irradiation.

In order to evaluate the effectiveness of BSM against UV radiation, p21 intensity was measured on a monolayer of keratinocytes, as the intensity directly correlates to cell damage. Additionally, fluorescent sphingomyelin (FSM) was added as a treatment because it was created to be an analog to BSM and allowed for visualization of sphingomyelin within the cell.

Differences in p21 intensities were observed with BSM and FSM showing a reduced p21 intensity compared to the no sphingomyelin case. FSM helped locate sphingomyelin within the cell and a mechanism was proposed for how it reduces cell damage. Lastly, high variation was seen between experimental designs. Further measures were needed to reduce this intra-subject standard deviation, so additional experimental parameters were tested such as min/max intensity values, cell count, and nucleus circularity to explain this variation.